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1.
监测草地资源的变化、把握草地资源变化的动向,有利于及时有效地保护我国的草地资源和草地生态环境,然而长时间跨度的规律监测不易实现。该文以5a为间隔,借助GIS技术和遥感数据,监测了1995-2010年我国西部新疆、西藏和青海3个代表性区域的草地资源变化情况。结果表明:1)草地退化是草地资源流失的主要原因。草地资源转出的主要方向为裸岩石砾地、戈壁和沙地等。要控制草地资源的流失,首先要阻止草地资源的退化。2)低覆盖度草地资源的保护更应引起重视。相比得到较好保护的高覆盖度草地,低覆盖度草地流失情况往往较严重。3)新疆面临着严重的草地资源流失问题,流失的草地资源面积高达8×106 hm2,且最后一个5年流失的面积占总流失面积的72%,亟须引起注意。西藏和青海的草地资源在研究时段后期趋于稳定。  相似文献   

2.
藏北高寒草地退化现状、原因与恢复模式   总被引:1,自引:0,他引:1  
藏北高寒草地系统生态脆弱且区位重要,草地退化和沙化的治理是目前学者们重点关注的领域之一。本文采用遥感解译、模型模拟、地面取样验证等相结合的方法,分析了藏北高寒草地生态系统退化的现状、趋势和原因,以实验为基础,总结了退化草地恢复的几种重要模式。数据分析表明:藏北羌塘高原轻度退化草地占62.0%,中度和重度退化草地占15.1%,1991年以来,退化面积快速增加,2000年以来重度退化面积增加趋势明显。藏北西部的草地轻度退化可能由气候暖千化所引起,而中部、东部的重度退化主要由超载过牧引起。总结出轻度退化草地的“封育”、中度退化草地的“施肥+封育”、重度退化草地的“补播+施肥+封育”三种草地恢复模式。提出了退化草地恢复和保护的间接途径“南草北上”生态工程的战略构想。  相似文献   

3.
藏北地区草地退化的时空分布特征   总被引:51,自引:2,他引:49  
根据草地退化国家标准和藏北地区草地退化实际情况以及遥感数据特征,选择草地植被盖度为草地退化的遥感监测指标,建立藏北地区草地退化遥感监测和评价指标体系,并对藏北地区近24年的草地退化进行遥感监测和评价。结果表明:藏北地区草地退化现状 (2004年) 十分严重,重度和极重度退化草地面积分别占草地总面积的8.0%和1.7%,区域草地退化指数 (GDI) 为1.86,接近中度退化等级;其中藏北地区冰川与雪山及其周围等气候变化较为敏感区域和交通要道沿线等人类活动较为频繁区域的草地退化相对严重;从1981年到2004年的近24年以来,藏北地区及其各个区域草地退化较为严重,其草地退化等级分布比例和草地退化指数年际波动较大,草地退化等级在轻度退化至重度退化等级之间波动;近几年藏北全地区总体草地退化情况及中部、东部和北部地区的草地退化具有更加严重的趋势,而西部地区草地退化状况则略有减缓趋势。  相似文献   

4.
基于卫星遥感信息的吉林省西部草地退化分析   总被引:9,自引:6,他引:9  
利用 1996年和 1986年秋季陆地卫星TM数据 ,将计算机监督分类与非监督分类识别方法结合应用进行草地的解译 ,改进算法 ,改善遥感图像的识别精度。试验研究结果表明 :吉林省西部草原生态环境在恶化 ,草地面积平均每年减少 4.5× 10 4hm2 ,草地退化严重 ,退化草地面积已占草地总面积的 81.1%,而且退化程度也在加重 ,中、重度退化草地比例明显提高 ,草地退化呈发展的趋势。  相似文献   

5.
吉林省西部草地土壤的化学元素含量及其特征研究   总被引:8,自引:3,他引:8  
对吉林省西部草地土壤化学元素含量研究表明,吉林省西部草地土壤中富钾少磷;钙、镁含量丰富;硼、铜、铁、锰含量在剖面上表现为向下增加;土壤中氮、磷、钾、钙、铜含量随草地退化程度的加深而减少;土壤中硅、钠含量丰富,显示出较强的沙化、盐碱化趋势,其含量随草地退化程度的加深而增加,钴含量随草地退化程度加深而降低;钡含量随草地退化程度的加深有增加的趋势;而稀土元素总量低于土壤背景值,并随着草地退化程度的加深其含量有减少的趋势。  相似文献   

6.
草地退化成为中国最主要的生态问题之一,研究其时空特征、影响以及驱动因子对退化草地治理和草地资源持续利用均有指导意义。从草地退化评价与监测研究的技术手段、基础、监测方法分类、常见的遥感分级指标及其局限性等方面的研究现状进行了综述,结果发现,目前草地退化遥感评价与监测工作中存在着草地退化与草地植被长势概念混淆、草地退化程度被"高估"、现有分级指标对某些特定的退化类型不敏感等问题,利用年降水量资料对植被覆盖度、地上生物量等现有分级指标进行校正,针对特定的退化类型,引入草地群落中退化指示植物的综合算术优势度、覆盖度的相对百分数等新的综合性分级指标并对其进行遥感反演是未来发展趋势,具有广阔的应用前景。  相似文献   

7.
 依据草地退化国家标准和黄河源区草地退化的实际情况,选取草地覆盖度、植株高度、地上生物量、牧草可食率、土壤有机质5个重要指标建立黄河源区玛多县草地植被退化监测和评价指标体系。利用遥感影像和GIS技术,结合实地调查和采样测定,对5个评价指标在遥感影像上进行反演,并进行图层的加权叠加,得出玛多县草地退化的时空特征。结果表明:玛多县草地在1994年已经出现了较为严重的退化现象,退化草地的空间分布格局已经基本形成,并且草地的退化过程一直在继续。2009年草地退化空间特征显示在气候变化较为敏感区域、河道两侧、鼠害严重以及靠近居民点等区域草地退化较为严重。通过对4期草地退化情况进行对比分析,发现1994-2001年间玛多草地植被退化情况最严重,重度退化面积高达1 355 943.30 hm2,占草地面积的86.53%。2001-2006年间和2006-2009年间重度退化、较大退化和中度退化草地的面积都下降较大,同时退化的速度已经有了较大缓和,黄河源头地区草地生态系统得到初步恢复  相似文献   

8.
国际草地资源遥感研究新进展   总被引:22,自引:1,他引:21  
系统地评论了国际上有关草地资源遥感研究的最近文献。首先,分析了草地遥感的可行性,确定了监测和评估草地资源最有效的光谱波段,阐述了各种遥感影像在草地资源调查与评估中的实用价值。之后,介绍了草地资源遥感的常用方法,即植被指数和其他指数法,对比和分析了各种指数在草地资源遥感应用中的有效性及应用范围。这些草地资源遥感的应用包括草地盖度监测与制图、生物量估算、草地退化监测及草地资源定量分析。最后,探讨了草地资源遥感的发展趋势,包括摄像遥感、高分辨率影像(如CASI,AVIRIS和IKONOS)和GPS的运用。此外,GIS的引入及其与数字影像处理的集合会使草地资源遥感由简单监测逐渐向动态预报和模拟过渡。这些研究新动向对国内相关科学家在选题时具有极大的参考意义。  相似文献   

9.
甘肃省肃南县草地过度放牧的社会经济成因分析   总被引:5,自引:3,他引:2  
我国草地资源位居世界第二位,但目前退化情况非常严重,已经成为牧区生态环境保护和经济发展的主要制约因素。导致草地退化的原因多种多样,其中自然因素是不可调控因素,但在近50年内并非为导致我国草地大面积退化的主要原因,实际上,人为因素才是最为主要的原因。在导致草地退化的诸多人为因素中,过度放牧被认为是造成草地退化的主要因素。通过对肃南县草地退化进行的农户问卷调查,结合有关统计资料,从农户角度阐释过度放牧行为产生的外在机制和内在机制,认为农户追求更高的家庭收入与现实经济状况之间的矛盾是导致其过度放牧行为产生的根本原因。  相似文献   

10.
本文以位于大兴安岭中山山地向科尔沁沙地过渡带的阿鲁科尔沁旗为研究对象,以1990年、2000年和2014年三期遥感影像数据为基础、结合阿鲁科尔沁旗统计年鉴、气象气候等资料,借助ENVI5.1和ARCGIS10.2软件,对阿鲁科尔沁旗草地退化现状特征、时空变化规律进行了研究,研究表明:2014年阿鲁科尔沁旗草地退化指数(GDI)为2.99,属于中度退化等级,研究区各个乡镇(苏木)草地退化指数(GDI)值在2.65~3.3之间,区域之间有一定的差异性,但整体上均处于中度退化的状态。草地退化状况空间分布特征为,南部和中南部地区草地退化较为严重,主要以中度退化草地为主,伴有重度退化草地;中部和中北部地势偏高的林牧区草地退化状况相对较轻,主要以轻度退化草地与中度退化草地相间分布,草地整体状况相对较好;最北端基本形成了无明显退化草地、轻度退化草地和中度退化草地相间分布的格局。  相似文献   

11.
BOOK REVIEWS     
Book Reviewed in this article: Development and Environment in Peninsular Malaysia . S. Robert Aiken, Colin H. Leigh, Thomas R. Leinbach, Michael R. Moss. The Rural-Urban Fringe: Canadian Perspectives . Ken B. Beesley and Lorne H. Russwurm, eds. Women and Development . Lourdes Benería, ed. The Border that Joins: Mexican Migrants and U.S. Responsibility . Peter G. Brown and Henry Shue, eds. Cities of the World: World Regional Urban Development . Stanley D. Brunn and Jack L. Williams, eds. Time Resources, Society, and Ecology: On the Capacity for Human Interaction in Space and Time (Vol. I, Preindustrial Societies). Tommy Carlstein. Urban Geography . David Clark. Spanish City Planning in North America . Dora P. Crouch, Daniel J. Garr, and Axel I. Mundigo. Not On Our Street: Community Attitudes to Mental Health Care . M. J. Dear and S. M. Taylor Unequal growth: Urban and Regional Employment Change in the U.K. Stephen Fothergill and Graham Gudgin. Agricultural Land in an Urban Society . Owen J. Furuseth and John T. Pierce. The Petroleum Industry in Oil-Importing Developing Countries . Fariborz Ghadar. Historical Understanding in Geography, An Idealist Approach . Leonard Guelke. Regional Planning in Europe . R. Hudson and J. R. Lewis, eds. Remote Sensing for Resource Management . Chris J. Johannsen and James L. Sanders, eds. Geography and The State . R. J. Johnston. Texas Graveyards: a Cultural Legacy . Tlrry G. Jordan. The Politics of Location: An Introduction . Andrew Kirby. A Social Geography of the City . David Ley. Energy and the Future . Douglas MacLean and Peter Brown, eds. The Natural Environment of Newfoundland Past and Present . A. G. Macpherson and J. B. Macpherson, eds. Tourism: Economic, Physical and Social Impacts . Alister Mathieson and Geoffrey Wall. Railroads and Land Grant Policy: A Study in Government Intervention . Lloyd J. Mercer. Progress in Rural Geography . Michael Pacione, ed. Progress in Urban Geography . Michael Pacione, ed. Models of Spatial Inequality: Settlement Patterns in Historical Archaeology . Robert Paynter. Natural Hazard Risk Assessment and Public Policy, Anticipating the Unexpected . William J. Petak and Arthur A. Atkisson. The Nature of Geomorphology . Alistair F. Pitty. Regional Conflict and National Policy . Kent A. Price Women and Spatial Change: Learning Resources for Social Science Courses . Arlene C. Rengert and Janice J. Monk, eds. Urban and Regional Analysis for Development Planning . Richard Rhoda. Rivers: Form and Process in Alluvial Channels . Keith Richards. This Remarkable Continent: An Atlas of United States and Canadian Society and Culture . John F. Rooney, Jr., Wilbur Zelinsky, and Dean R. Louder, gen. eds. The Origins of Open-Field Agriculture . Trevor Rowley, ed. Residential Location Determinants of the Older Population . Gundars Rudzitis. Borderland Sourcebook: A Guide to the Literature on Northern Mexico and the American Southwest . Ellwyn R. Stoddard, Richard L. Nostrand, and Jonathan P. West, eds. Arctic and Antarctic . David Sugden. Tall Timbers Ecology and Management Conference, February 22–24, 1979, Proceedings No. 16 . Graphic Communication and Design in Contemporary Cartography (Progress in Contemporary Cartography , Vol. II). D. R. Fraser Taylor, ed. Living with Energy Shortfall: A Future for American Towns and Cities . Jon Van Til. The United States: Habitation of Hope . J. Wreford Watson. Air Photo Interpretation for Archaeologists . D. R. Wilson. Urban and Rural Change in West Germany . Trevor Wild, ed. Population and Resources . Harry Robinson.  相似文献   

12.
<正>1 Introduction In 2013,Chagusaba,which is traditional tea-grass integrated system in Shizuoka,were accepted as new world heritage site of agriculture.Shizuoka prefecture occupies a variety of elevations,from 0 to 3000m or more above sea level.Because of the diversity of land features and climates,this area produces 167 agricultural commodities.In addition,a lot of traditional agriculture and over200 local native varieties of crops have been conserved in Shizuoka  相似文献   

13.
<正>There are more than 10000 years of agricultural development history in the world that has provided very fruitful and ingenious traditional knowledge and experiences reflecting the evolution of humanity and the nature.In2002,the Food and Agriculture Organization of the United Nations(FAO)initiated an international partnership initiative of"Conservation and Adaptive Management of Globally Important Agricultural Heritage Systems  相似文献   

14.
15.
BOOK REVIEWS     
Book Reviewed in this article: Geography and the Third World. International Seminar, 14–18 May 1980, Kuala Lumpur, Malaysia . Ishmail Ahmad and Jamaluddin Md Jahi, eds. The Growth Dilemma: Residents' Views and Local Population Change in the United States . Mark Baldassare. Sport and Place: A Geography of Sport in England, Scotland & Wales . John Bale. The Deindustrialization of America: Plant Closings, Community Abandonment, and the Dismantling of Basic Industry . Barry Bluestone and Bennett Harrison. Selected Essays 1963–1975: Carl O. Sauer . Bob Callahen, ed. Housing and Planning in the Countryside . G. Clark. Conflict, Politics and the Urban Scene . Kevin R. Cox and R. J. Johnston, eds. Thematic Maps: Their Design and Production . David J. Cuff and Mark T. Mattson. Wine: A Geographic Appreciation . Harm Jan de Blij. USSR in Maps . J. C. Dewdney. Political Geography: A Contemporary Perspective . Ramesh D. Dikshit. Rethinking Human Adaptation . Rada Dyson-Hudson and Michael A. Little, eds. Sacred Sands: The Struggle for Community in the indiana Dunes . J. Ronald Engel. Geography of the Biosphere . A. Furley and Walter W. Newey. Disaster and Reconstruction . Robert Geipel. Glasgow: The Making of a City . Andrew Gibb. Design for Arid Regions . Giden S. Golany, ed. Urbanization and Cancer Mortality: The United States Experience, 1950–1975 . Michael R. Greenberg. Geology in the Nineteenth Century: Changing Views of a Changing World . Mott T. Greene. Colonización y Destrucción de Bosques en Panamá . Stanley Heckadon Moreno and Alberto McKay, eds. Urban Geography: A First Approach . David T. Herbert and Colin J. Thomas. The Visual and Spatial Structure of Landscapes . Tadahiko Higuchi. Climate from Tree Rings . M. K. Hughes, P. M. Kelly, J. R. Pilcher, and V. C. LaMarche, Jr., eds. The structure of Nineteenth Century Cities . James H. Johnson and Colin G. Pooley, eds. The American Planner: Biographies and Recollections . Donald A. Krueckeberg, ed. Urban Land Policy For the 1980s, the Message for State and Local Government . George Lefcoe, ed. Regional Planning: Evolution, Crisis and Prospects . Gill C. Lim, ed. Relevance and Ethics In Geography . Bruce Mitchell and Dianne Draper. China: The Geography of Development and Modernization . Clifton W. Pannell and Laurence J. C. MA. The Urban Retailing System . Robert B. Potter. Hants. Nonconventional Energy Resources . Philip R. Pryde. Caribbean Migrants: Environment and Human Survival on St. Kitts and Nevis . Bonham C. Richardson. Population and Resources . Harry Robinson. East Los Angeles: History of A Barrio . Ricardo Romo. Integrated Impact Assessment . Frederick A. Rossini and Alan L. Porter, eds. Environmental Aesthetics: Essays in Interpretation . Barry Sadler and Allen Carlson, eds. Earthwatch . Charles Sheffield. Field Techniques and Research Methods in Geography . Robert H. Stoddard. Haiti: Land of Poverty . Robert J. Tata. Weathering and Erosion: Sources and Methods in Geography . Stephen T. Trudgill. Once Beneath the Forest. Prehistoric Terracing in the Río Bec Region of the Maya Lowlands . B. L. Turner, II. The Historical Geography of Scotland since 1707 . David Turnock.  相似文献   

16.
BOOK REVIEWS     
Book Reviewed in this article: The City in Cultural Context . John Agnew, John Mercer, David Sopher, eds. Soils and Geomorphology Peter W. Birkeland. Urbanization and Settlement Systems, International Perspectives . L. S. Bourne, R. Sinclair, and K. Dziewoński. eds. An Introduction to Urban Historical Geography . Harold Carter. Overshoot, The Ecological Basis of Revolutionary Change . William J. Catton, Jr. Rivers of the World . Eberhard Czaya. Jewish Communities in Frontier Societies: Argentina, Australia and South Africa . Daniel J. Elazar with Peter Medding. Color in Public Spaces: Toward a Communication-Based Theory of the Urban Built Environment. Kenneth E. Foote. Spatial Statistics and Models. Gary L. Gaile and Cort J. Willmott, eds. Mega-Geomorphology. Rita Gardner and Helen Scoging, eds. Technological Change and Regional Development. Gillespie, ed. The Arid Lands: Their Use and Abuse. R. L. Heathcote. The Location of Industry in Britain. A. G. Hoare. Groundwater as a Geomorphic Agent . R. G. LaFleur, ed. Rural Public Services: International Comparisons. Richard E. Lonsdale and Gyorgy Enyedi, eds. Saving Water in a Desert City. William E. Martin, Helen M. Ingram, Nancy K. Laney, and Adrian H. Griffin. Water Resources: Distribution, Use and Management. John R. Mather. Transnationals and the Third World: The Struggle for Culture. Armand Mattelart. South Hadley, MA: USGS Digital Cartographic Data Standards. R. B. McEwen, R. E. Witmer, and B. S. Ramey, eds. The Ecosystem Concept in Anthropology. Emilio F. Moran, ed. Boulder, CO: Women, Men, and the International Division of Labor. June Nash and Maria Patricia Fernandez-Kelly, eds. Nuclear Power: Assessing and Managing Hazardous Technology. Martin J. Pasqualetti and K. David Pijawka, eds. Mary Somerville and the Cultivation of Science 1815-1840. Elizabeth Chalmers Patterson. An Introduction to Coastal Geomorphology. John Pethick. Late Quaternary Environments of the United States , Vol. 1, The Late Pleistocene. Stephen C. Porter, ed. Planning and Ecology. R. D. Roberts and T. M. Roberts, eds. Regionalism and the Pacific Northwest. William G. Robbins, Robert J. Frank, and Richard E. Ross, eds. Environment and Health. Anthony J. Rowland and Paul Cooper. Sunbelt/Snowbelt: Urban Development and Regional Restructuring. Larry Sawers and William K. Tabb, eds. The Bad Earth. Environmental Degradation in China. Vaclav Smil. Armonk, NY: Voyage into Substance: Art, Science, Nature, and the Illustrated Travel Account, 1760–1840. Barbara Maria Stafford. The Institute of British Geographers: The First Fifty Years. Robert W. Steel. Visions of the Past. Christopher Taylor and Richard Muir. Glacial Lake Agassiz. J. T. Teller and Lee Clayton, eds. The Tule Breakers: The Story of the California Dredge. John Thompson and Edward A. Dutra. The Balkan City 1400–1900. Nikolai Todorov. Explanation, Prediction and Planning: the Lowry model. Michael J. Webber. Mercedes Reales: Hispanic Land Grants of the Upper Rio Grande Region. Victor Westphall. The World Atlas of Revolutions. Andrew J. M. Wheatcroft. The West European City, A Social Geography. Paul White. Urban Elites and Mass Transportation. J. Allen Whitt. Princeton, NJ: Urban Life In Contemporary China. Martin King Whyte and William L. Parish. The Demand for Energy in the Soviet Union. David Wilson. London and Canberra: Rethinking Geographical Inquiry. J. David Wood, ed.  相似文献   

17.

Reviews of geographic software in this article:

DEMO-GRAPHICS: WORLD POPULATIONS AND PROJECTIONS.

ESP

GAUSS.

CEMODEL S. Damus

LIMDEP. William H. Greene

MICROSTAT 4.1

OTIS

PCIPS. (Personal Computer Image Processing System). H.J. Meyers and R. Bernstein.

REGRESSION ANALYSIS OF TIME SERIES (RATS)

SPSS/PC+

URBAN DATA MANAGEMENT SOFTWARE (UDMS)  相似文献   

18.
BOOK REVIEWS     
Book Reviewed in this article: Rabat: Urban Apartheid in Morocco . Janet Abu -Lughod . Marketplaces in a Developing Country: The Case of Western Nigeria . Isaac Ayinde Adalemo . Farming Development and Space: A World Agricultural Geography . Bernd Andreae . Section and Party: A Political Geography of American Presidential Elections, from Andrew Jackson to Ronald Reagan . J. Clark Archer and Peter J. Taylor . Women and Space: Ground Rules and Social Maps . Shirley Ardener , ed. European Progress in Spatial Analysis . R. J. Bennett , ed. The Origins of Academic Geography in the United States . Brian W. Blouet Geographic Perspectives on Global Problems . Ronald Reed Boyce . Seasonal Dimensions to Rural Poverty . Robert Chambers , Richard Longhurst and Arnold Pacey eds. The New Nationalism and the Use of Common Spaces: Issues in Marine Pollution and the Exploitation of Antarctica . Jonathan I. Charney , ed. Communications Tomorrow: The Coming of the Information Society . Edward Cornish , ed. The Design of Suburbia . Arthur Edwards . Explorer on the Northern Plains: Lieutenant Gouverneur K. Warren's Preliminary Report of Explorations in Nebraska and Dakota in the Years 1855–56–57. With an Introduction by Frank N. Schubert . The Changing Climate: Responses of the Natural Flora and Fauna . Michael J. Ford . Essentials of Physical Geography . Robert E. Gabler , Robert J. Sager , Sheila Brazier , and Daniel L. Wise. The Road to Jaramillo . William Glen . Valued Environments . John R. Gold and Jacquelin Burgess , eds. Proximity and Preference: Problems in the Multidimensional Analysis of Large Data Sets . Reginald G. Golledge and John N. Rayner , eds. A Search for Common Ground . Peter Gould and Gunnar Olsson , eds. Geography: Its History and Concepts . Arild Holt -Jensen . A Population Geography . Huw R. Jones . The Human Mosaic: A Thematic Introduction to Cultural Geography, 3rd ed. Terry G. Jordan and Lester Rowntree . Urban Social Geography: An Introduction . Paul Knox . The Anatomy of Job Loss: The How, Why and Where of Employment Decline . Doreen Massey and Richard Meegan . The Information Society as Post-Industial Society . Yoneji Masuda . Map Librarianship, 2nd ed. Harold Nichols . India: Cultural Patterns and Processes . Allen G. Noble and Ashok K. Dutt , eds. The God that Limps: Science and Technology in the Eighties . Colin Norman . Geography: An Introductory Perspective . Robert E. Norris , Keith D. Harries and John D. Vitek . The Politics of Technology Assessment . David M. O'Brien and Donald A. Marchand . Ethnic Segregation in Cities . Ceri Peach , Vaughan Robinson and Susan Smith , eds. Churches and Church Membership in the United States, 1980 . Bernard Quinn , Herman Anderson , Martin Bradley , Paul Goetting and Peggy Shriver . Energy in Australia: Politics and Economics . Hugh Saddler . Development from Above or Below? The Dialectics of Regional Planning in Developing Countries . Walter B. Stóuhr and D. R. Fraser Taylor , eds. Human Impact on the Ecosystem . Joy Tivy and Greg O'Hare . Plants and People: Vegetation Change in North America . Thomas R. Vale . The Mapmakers: The Story of the Great Pioneers in Cartography from Antiquity to the Space Age . John Noble Wilford .  相似文献   

19.
Desertification is a global phenomenon that affects about two billion people. It occurs in arid zones where the annual precipitation is below 400 mm, partic- ularly in the marginal areas of the world's largest deserts. It is a result of water and wind erosion, over- grazing, global warm-ing, improper soil cultivation, and increased pressure ot population growth, and it causes degradation of soil and natural and agricultural vegetation. The direct result is less food for people and livestock, which influences pop- ulation and animal husbandry fluctuations. Despite ef- forts to combat and reduce desertification, the affected areas are annually increasing.  相似文献   

20.
BOOK REVIEWS     
Book Reviewed in this article: The Rice Economy of Asia . Randolph Barker and Robert W. Herdt with Beth Rose. Using Microcomputers: A Guidebook for Writers, Teachers, and Researchers in the Social Sciences . Blaine A. Erie—the Lake that Survived . Noel M. Burns. Geology and Society . Donald R. Coates. Caves and Karst of Kentucky . Percy H. Dougherty, ed. Altered Harvest: Agriculture, Genetics, and the Fate of the World's Food Supply . Jack Doyle. The Middle East and North Africa, A Political Geography . Alasdair Drysdale and Gerald H. Blake. Clamor at the Gates. The New American Immigration . Nathan Glazer, ed. Development and the Landowner: An analysis of the British experience . Robin Goodchild and Richard Munton. Discovering Landscape in England and Wales . Andrew Goudie and Rita Gardner. The Modern Plantation in the Third World . Edgar Graham and Ingrid Floering. Social Relations and Spatial Structures . Derek Gregory and John Urry, eds. The World Food Problem 1950–1980 . David Grigg. Costa Rica: A Geographical Interpretation in Historical Perspective . Carolyn Hall. The Urbanization of Capital: Studies in the History and Theory of Capitalist Urbanization . David Harvey Consciousness and the Urban Experience: Studies in the History and Theory of Capitalist Urbanization . David Harvey. Reviving Main Street . Deryck Holdsworth, ed. Rural Roads and Poverty Alleviation . John Howe and Peter Richards, eds. Uneven Development in Southern Europe: Studies of Accumulation, Class, Migration and the State . Ray Hudson and Jim Lewis, eds. Karst Geomorphology . J. N. Jennings. The Geomorphology of North-west England . R. H. Johnson, ed. Climate Impact Assessment: Studies of the Interaction of Climate and Society . Robert Kates, Jesse Ausubel, Mimi Berberian, eds. Public Service Provision and Urban Development . Andrew Kirby, Paul Knox, and Steven Pinch, ed. State and Market: The Politics of the Public and the Private . Jan-Erik Lane, ed. Living Cities . Twentieth Century Fund Task Force on Urban Preservation Policies. World Climatic Systems . John G. Lockwood. Urban Ethnicity in the United States. New Immigrants and Old Minorities . Lionel Maldonaldo and Joan Moore, eds. Culture and Conservation: The Human Dimension in Environmental Planning . Jeffrey A. McNeely and David Pitt, eds. The Andean Past. Land, Societies, and Conflicts . Magnus Mörner. Gaia: An Atlas of Planet Management . Norman Myers, ed. Progress in Industrial Geography . Michael Pacione, ed. Progress in Political Geography . Michael Pacione, ed. Rivers and Landscape . Geoff Petts and Ian Foster. Urbanization and Planning in the 3rd World: Spatial Perceptions and Public Participation . Robert B. Potter. One Island, Two Nations? A Political Geographical Analysis of the National Conflict in Ireland . D. G. Pringle. Circulation in Third World Countries . R. Mansell Prothero and Murray Chapman. The Ozarks Outdoors: A Guide for Fishermen, Hunters, and Tourists . Milton D. Rafferty. Suburban Burglary: A Time and a Place for Everything . George Rengert and John Wasilchick. Geomorphology and Soils . K.S. Richards, R.R. Arnett, and S. Ellis, eds. The Homes and Homeless of Post-War Britain . Frederick Shaw. Indochinese Refugees in America . Paul J. Strand and Woodrow Jones, Jr. Wild Horses and Sacred Cows . Richard Symanski. Forever Wild: Environmental Aesthetics and the Adirondack Forest Preserve . Philip G. Terrie. The Regional Economic Impact of Technological Change . A.T. Thwaites and R.P. Oakey, eds. The Good Life . Yi-Fu Tuan.  相似文献   

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